JP2786458B2 - ISDN telephone terminal - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an ISDN telephone terminal using ISDN as a transmission line.

[Prior Art] In recent years, ISDN (Integrated Services Digital Communication Network) has been improved, and data terminal devices for exchanging data using this ISDN have been gradually put into practical use.

This ISDN will replace the conventional PSTN (Public Telephone Network) in the future, and ISDN telephone terminals that perform the same functions as conventional telephone terminals have come into practical use.

[Problems to be Explained by the Invention] By the way, a signal channel for exchanging various signals with a network in a call setup procedure and the like and two information channels are multiplexed on an ISDN subscriber line. Such ISDN telephone terminals are required to have a function of effectively utilizing such multiplexed information channels.

The present invention has been made in view of such circumstances, and realizes a transfer function that can transfer a call detected at that time to another ISDN telephone terminal when the operator of the ISDN telephone terminal is absent or the like. It aims to provide ISDN telephone terminals.

[Means for Solving the Problems] The present invention relates to an ISDN telephone terminal using ISDN as a transmission path, a transfer destination input means for inputting a transfer destination operation,
Transfer destination storage means for storing the transfer destination input from the transfer destination input means, transfer cancel operation means for canceling the transfer mode set in the other terminal, and responding to the calling terminal when the incoming call is detected, to the calling terminal A call to the destination transfer in a state where the transfer destination responds to the incoming call, responds to the incoming call to the calling terminal, and transfers the information received via the first information channel set between the calling terminal and the transfer terminal. While performing transfer control to send to the transfer destination via the set second information channel and to send information received via the second information channel to the calling terminal via the first information channel, incoming call control is performed. Control means for preventing the transfer control from being performed after receiving the transfer release information via the signal channel from the originating terminal when the transfer release operating means is operated from the calling terminal at the time of detection. Than it is.

Further, in an ISDN telephone terminal using ISDN as a transmission path, a transfer destination input means for operating and inputting a transfer destination, a transfer destination storage means for storing a transfer destination input from the transfer destination input means, and setting in another terminal Transfer canceling operation means for canceling the transfer mode being set, and calling the destination transfer in a state in which a call signal is responded to the calling terminal when an incoming call is detected. And sends the information received via the first information channel set between the terminal and the transfer terminal to the transfer destination via the second information channel set between the terminal and the transfer terminal. Transfer control for transmitting the received information to the calling terminal via the first information channel, and transferring cancellation information by operating the transfer canceling operation means from the calling terminal when an incoming call is detected. When receiving over the signal channel, and thereafter, as well as to not to perform the above-described transfer control, after the transfer release, when receiving the information representing the transfer reconfiguration from the calling terminal when the call detected, thereafter,
The apparatus is provided with control means for resetting the transfer control.

Further, in an ISDN telephone terminal using ISDN as a transmission path, a transfer destination input means for operating and inputting a transfer destination, a transfer destination storage means for storing a transfer destination input from the transfer destination input means, and setting in another terminal A call release operation means for canceling the transfer mode being performed, and calling the destination transfer in a state where a call signal is responded to the calling terminal when an incoming call is detected, and when the transfer destination answers the incoming call, answering the incoming call to the calling terminal,
Sending the information received via the first information channel set up with the calling terminal to the transfer destination via the second information channel set up with the transferring terminal and the second information channel While transmitting control to transmit the information received via the first information channel to the calling terminal via the first information channel, the calling terminal transmits a signal indicating that the transfer canceling operation means has been operated by the calling terminal when an incoming call is detected. When receiving via the channel, the transfer control is not performed thereafter, and when the transfer destination is busy and the call is not answered, the call connection with the calling terminal is not performed and the transfer destination can answer the call. , A control means is provided for notifying that a call has been made from the calling terminal.

[Operation] Therefore, since the call of the calling terminal can be transferred to a predetermined transfer destination, even if the operator is absent, the call between the operator of the calling terminal and the operator of the own terminal can be performed, and another call can be made. Since the transfer operation can be stopped from the terminal, when the transfer operation becomes unnecessary, the transfer operation can be stopped immediately, which is very convenient. Further, since the remote operation can be performed to reset the transfer operation after the transfer is canceled, the operation of canceling and resetting the transfer operation becomes very convenient. If the transfer destination is busy, the transfer destination notifies the transfer destination that a call has been made from the calling terminal when the transfer destination is ready to respond. And the operator of the calling terminal can make a desired call.

Hereinafter, an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 shows an ISDN telephone according to one embodiment of the present invention.

In FIG. 1, a CPU (central processing unit) 1
A ROM (read only memory) 2 executes control processing of the entire telephone and line control processing of the ISDN basic interface function. The ROM 1 has a control processing program to be executed by the CPU 1 and various control programs necessary for the control processing program. A RAM (random access memory) 3 stores various information unique to the ISDN telephone, such as a telephone number of a transfer destination.

The operation display unit 4 is used to operate the ISDN telephone, and includes various operation keys and a display.
The tone generating circuit 5 is for generating various tone signals such as a ringing tone for calling an operator when an incoming call is detected and a beeping sound for calling attention to the operator. 5 is for outputting various tone signals generated from.

The ISDN interface circuit 7 uses this ISDN telephone
To connect to the network terminating equipment (NT)
The control unit 8 is a layer 2 of the basic interface function of ISDN.
The audio signal converter (CODEC) 9 converts an analog audio signal for a call into an ISD signal.
The handset 10 is for converting into a digital signal that can be handled by N and transmitting the digital signal, and the handset 10 is for talking. The hook signal of the handset 10 is CP
Output to U1.

The CPU 1, the ROM 2, the RAM 3, the operation display unit 4, the tone generation circuit 5, the ISDN interface circuit 7, the LAPD control unit 8, and the audio signal conversion unit 9 are connected to the system bus 11, Various types of information exchanged between the devices are performed via the system bus 11.

FIG. 2 shows an example of the operation display unit 4 of the ISDN telephone.

In the figure, a numeric keypad 4a is for inputting numerical information such as a destination telephone number and a sub-address number, and a set key 4b is used to specify input information from the numeric keypad 4a and designate a timing to be taken into an ISDN telephone. The clear key 4c is for erasing input information input from the numeric keypad, and the transfer destination setting key 4d
Is used to set a transfer mode for transferring an incoming call to another ISDN telephone when an incoming call is detected by this ISDN telephone, and a transfer release key 4e is used to set a transfer mode set for another ISDN telephone. The transfer reset key 4f is used for inputting the transfer cancel function to cancel the transfer.
This is for inputting a transfer reset function for setting (resetting) a transfer mode to another ISDN telephone.

The lamp 4g indicates that the ISDN telephone is set to the transfer mode, and the liquid crystal display 4h displays various kinds of guidance information from the ISDN telephone to the operator and numerical information operated and input from the ten keys 4a. Is displayed and output. In this embodiment, the set key 4b and the clear key 4c are used as keys for responding to the guidance message.

In addition, a monitor speaker 6 is built in below the transfer reset key 4f, and a portion that can accommodate the handset 10 is secured on the left side of the housing. Note that the handset 10 is on-hook when housed, and the handset 10 is off-hook when picked up. The hook state is detected by a hook switch (not shown) and notified to the CPU 1 as a hook signal.

Here, a basic transmission procedure performed by an ISDN telephone during a call will be described.

As shown in FIG. 3, the calling terminal first sends a call setup message SETUP to ISDN to request a call setup with the called terminal, and the ISDN sends a call setup message SETU to the designated called terminal.
Send P to make a call.

Upon receiving the call setup message SETUP, ISDN sends a call setup acceptance message CALL_PROC for notifying the call setup status.
To the calling terminal.

When the called terminal detects an incoming call, it starts ringing to call the operator of the own terminal and sends a calling message ALERT to ISDN.
To the calling terminal to notify that the calling of the called terminal has started. Note that the call message ALERT is repeatedly output at an appropriate cycle.

When the operator who hears the ringing tone picks up the handset 10 and detects that the user has gone off-hook, the called terminal stops outputting the ringing message ALERT and turns off the response message CONN.
To the ISDN, and the ISDN sends a response message CONN to the calling terminal to notify that the called terminal has accepted the call.

Also, ISDN sends a response confirmation message CONN_ACK to the called terminal.
To confirm the response of the called terminal, at which point an information channel for data transmission is established between the calling terminal and the called terminal.

Thus, a call can be made between the calling terminal and the called terminal, and a call can be made between the respective operators.

When the call ends and the calling terminal operator goes on-hook first, the calling terminal sends a disconnect message DISC to the IS.
It sends it to the DN to request the release of the information channel, and the ISDN sends a disconnection message DISC to the destination terminal to notify the restoration of the information channel.

As a result, when the destination terminal responds to the ISDN with a release message REL for notifying the completion of the channel disconnection, the release message REL is transmitted from the ISDN to the calling terminal. When the channel release is completed, the calling terminal issues a release completion message REL_COMP to the ISDN.
To notify that fact, ISDN sends a release completion message REL_COMP to the destination terminal, the release of the information channel is established, and the information channel set between the calling terminal and the destination terminal Is completely released.

In this way, an information channel is set between the calling terminal and the called terminal, a call is made between operators, and the information channel is released.

Also, after the end of the call, the operator of the called terminal can go off-hook first to release the information channel. In this case, a disconnection message DISC is sent from the called terminal to request the release of the information channel.

Next, necessary for realizing the transfer function of the present embodiment,
Call setup message SETUP and release complete message REL_C
The contents of OMP will be described.

First, as shown in FIG. 4 (a), each message is a protocol identifier for identifying a protocol specification (format, sequence, etc.) defining a layer 3 call control message, and which call is involved in the message. Call number to identify the message, message type to identify the content of each message,
Mandatory information elements that are always added to each message,
And an additional information element added to each message as needed. Note that 0, 1, or a plurality of essential information elements are set according to the message type, and 0, 1, or a plurality of additional information elements are arranged according to the situation.

The call setup message SETUP has "transmission capability" as an essential information element and "terminal function", "calling number", "calling number", and "user" as additional information elements, as shown in FIG.・ It has information elements such as "user".

The release completion message REL_COMP has “reason display” as an essential information element and “display” and “user / user” as additional information elements, as shown in FIG.

 Here, the outline of each information element will be described.

The “transmission capability” information element uses an information transfer capability indicating whether the content of information to be transmitted is voice, unrestricted digital information, restricted digital information, 3.1KHz audio, 7KHz audio, or video. The switching function includes a transfer mode indicating whether the switching function is a circuit switch or a packet switch, an information transfer speed indicating an information transfer speed, information indicating an information transfer mode, and information indicating a user information protocol.

The "terminal function" information element is used to indicate the function of the stimulus mode terminal to the network.

The “calling number” information element indicates the ISDN address (telephone number) of the calling terminal, and the “calling number” information element indicates the IS of the called terminal.
Indicates the DN address.

The "reason indication" information element is used to describe the reason for generating a certain message, prepare diagnostic information when there is a procedural error, and indicate the source of the reason.

The "display" information element is used for displaying various display information transmitted from the network to the terminal, such as a usage fee, on the terminal.

The “user / user” information element is used for transmitting information between users, and the content of this information element is:
It is transmitted transparently to the partner terminal without being interpreted by the network.

With the above-described configuration, for example, an operation in a case where the transfer function of receiving an incoming call to his / her own telephone at the destination telephone in the absence of the operator will be described. It is assumed that each telephone terminal in the following description has the same configuration as the ISDN telephone of FIG.

At this time, the operator first turns on the transfer destination input key 4d of the operation display unit 4.

As a result, the CPU 1 of the ISDN telephone displays, for example, a guidance message "Please enter the transfer destination telephone number and turn on the set key", and the operator inputs the transfer destination telephone number from the numeric keypad 4a. Wait for input to turn on set key 4b.

When the operator finishes the operation, the telephone number input at that time is stored as a transfer destination telephone number, a transfer mode is set, and a lamp 4g indicating that the transfer mode is set is displayed. Light up.

A case where an ISDN telephone set to this transfer mode (hereinafter referred to as a transfer terminal) is called from another ISDN telephone in this state will be described.

In this case, as shown in FIG. 5, when the calling terminal sends a call setup message SETUP in which this transfer terminal is set to the destination to ISDN, the call setup message SE is sent from ISDN to this transfer terminal.
A TUP is sent and a transfer terminal is called.

The transfer terminal stores the calling number of the call setup message SETUP, starts responding to the call message ALERT,
At this time, since the transfer mode has been set, the call setup message in which the transfer destination telephone number stored at that time is set as the called number and the telephone number of the own terminal is set as the calling number
Send SETUP to ISDN to call the transfer destination terminal.

Note that the call setup procedure between the calling terminal and the transfer terminal and the call setup procedure between the transfer terminal and the transfer destination terminal are performed independently.

This allows the call setup message to be sent from the ISDN to the destination terminal.
SETUP is transmitted, and the destination terminal is called.

Upon receiving the call setup message SETUP, the transfer destination terminal
The generation of a ringing tone for calling an operator is started, and the transmission of a calling message ALERT to ISDN is started.

When the operator who hears the ringing tone picks up the handset 10 and detects an off-hook, the transfer destination terminal sends a response message CONN to the transfer terminal.

Upon receiving the response message CONN according to the call setup procedure at the transfer destination terminal, the transfer terminal sends out a response message CONN of the call setup procedure at the caller terminal to ISDN.

ISDN establishes an information channel between a calling terminal and a transfer terminal and between a transfer terminal and a transfer destination terminal, and notifies the establishment of each information channel by a response acknowledgment message CONN_ACK.

Thereby, an information channel is established between the originating terminal and the transfer terminal and between the transfer terminal and the transfer destination terminal.

Thereafter, for example, when the information channel B1 is allocated to the calling terminal and the information channel B2 is
The received signal received via B1 is used as it is for information channel B2.
And transmits the received signal received via the information channel B2 as it is to the information channel B1.

That is, the voice signal from the operator of the calling terminal is transmitted to the transfer destination terminal via the transfer terminal, and the voice signal from the operator of the transfer destination terminal is transmitted to the call destination terminal via the transfer terminal. Communication between the operator of the terminal and the operator of the transfer destination terminal becomes possible.

When the call ends and the operator of the calling terminal and the operator of the transfer destination terminal return the handset 10 at any timing, the disconnection message DISC is sent from the calling terminal and the transfer destination terminal at the timing of the on-hook.
Sent to DN.

Accordingly, upon receiving the disconnection message DISC in the call setup procedure of the calling terminal, the transfer terminal starts the call recovery procedure with the calling terminal, and independently of the call setup procedure of the transfer destination terminal. When the disconnection message DISC is received in step (1), a call recovery procedure is started with the transfer destination terminal to recover each call connection.

In this way, when the transfer terminal is called from the calling terminal, the transfer terminal calls the transfer destination terminal while holding the call, and when the transfer destination terminal answers the incoming call, the transfer terminal Answer the incoming call.

Thus, when the ISDN establishes an information channel between the calling terminal and the transfer terminal and between the transfer terminal and the transfer terminal, respectively, the transfer terminal interfaces between the call terminal and the transfer destination terminal. In this case, a call can be made between the operator of the calling terminal and the operator of the transfer destination terminal.

When the transfer terminal receives the disconnection message DISC in the call setup procedure of the calling terminal, the transfer terminal proceeds to a procedure of releasing the call connection with the caller, and also transmits the disconnection message DISC in the call setup procedure of the transfer destination terminal. Upon reception, the procedure proceeds to a procedure for releasing the call connection with the transfer destination terminal side, and the call is released independently.

By the way, when the transfer destination terminal is in a busy state, as shown in FIG. 6, the transfer destination terminal receiving the call setup message SETUP ignores the call and sends a predetermined response message. I won't do it.

At this time, the ISDN sends a call message ALERT to the transfer terminal.
However, since the response message CONN is not received from the transfer destination terminal even after a certain time elapses, the release message REL containing the "reason indication" information element indicating that there is no response from the destination terminal at that time Send out. Upon receiving the release message REL, the transfer terminal responds with a release completion message REL_COMP and ends the call setup procedure on the transfer destination terminal side.

On the other hand, when the transfer terminal receives the release message REL in the call setup procedure of the transfer destination terminal, it sends out a disconnect message DISC in the call setup procedure of the caller, executes the call release procedure with the caller, and performs call release. Release the call connection with the terminal.

In this way, if the transfer operation fails, the transfer terminal sets the call setup message SETU
Send to P transfer destination terminal. At this time, the call setup message S
In the "user / user" information element of the ETUP, information indicating that an incoming call has been detected and the telephone number of the calling terminal at that time are set.

The transfer destination terminal receives the call setup message SE received from ISDN.
When the TUP is analyzed and the "user / user" information element includes information indicating that the incoming call has been detected,
At that time, a release completion message REL_COMP is sent to ISDN to release the call connection.

In addition, the release completion message REL_COMP “user /
The call setup message SETU as the content of the "user" information element
Set response information indicating that you understand P.

As a result, the release completion message is sent from the ISDN to the transfer terminal.
REL_COMP is sent and the call ends.

Further, the transfer terminal checks the contents of the “user / user” information element of the release completion message REL_COMP, and confirms that the transfer destination terminal has returned appropriate response information.

On the other hand, upon ending the transmission of the release completion message REL_COMP, the transfer destination terminal outputs the beep sound generated from the tone generation circuit 5 from the speaker 6 to alert the operator, and displays, for example, " [Calling number]
Received a call from [Calling Phone Number]. Is displayed, and the operator is notified that the call has been matched from the calling terminal to the transfer terminal. Here, [Calling number]
The contents of the "calling number" information element of the call setup message SETUP at that time are displayed, and the contents of the "calling terminal telephone number" are included in the "user / user" information element. Displays the contents of the phone number of the calling terminal.

In this way, if the transfer destination terminal was busy at the time of the transfer processing, the call from the calling terminal to the transfer terminal was made when the transfer destination terminal became available for answering a call. Is notified to the transfer destination terminal, displayed on the transfer destination terminal, and notified to the operator.

Therefore, the operator of the transfer destination terminal can make a call to the calling terminal, so that it is possible to talk with the operator of the calling terminal.

Further, the transfer terminal transmits a call release message REL_COMP in which the predetermined response information is included in the “user / user” information element.
Until the transfer destination terminal receives the message, the call setup message SETUP having the same contents is repeatedly transmitted at regular time intervals, and the transfer destination destination is re-called.

Such processing is performed even when the transfer terminal is using one information channel when a call is made from the calling terminal.

In this case, when the call setup message SETUP is received, the call connection is released in response to the immediate release completion message REL_COMP, and when an appropriate time elapses, the "user
In the "user" information element, information indicating that the incoming call has been detected and a call setup message SETUP in which the telephone number of the calling terminal at that time is set are sent to ISDN, and the transfer destination terminal is called.

By the way, release of the transfer mode of the transfer terminal and resetting of the transfer destination can be performed as follows.

That is, when the operator cancels the transfer mode of the ISDN telephone of the own terminal, the transfer destination input key 4d may be turned on again.

Thereby, the CPU 1 releases the transfer mode and deletes the transfer destination telephone number.

To release the transfer mode of the transfer terminal from another ISDN telephone, the transfer release key 4e is turned on.

As a result, the ISDN telephone displays, for example, guidance on the liquid crystal display 4h that "Please enter the telephone number of the telephone whose transmission mode is to be released and turn on the set key 4b."

Thus, when the operator operates the numeric keypad 4a to input the telephone number of the transfer terminal whose communication mode is to be canceled and turns on the set key 4b, the ISDN telephone starts a calling operation.

That is, as shown in FIG. 7, the "calling number" information element contains the telephone number of the terminal itself, the "calling number" information element contains the telephone number of the transfer terminal, and the "user / user" information element releases the transfer mode. A call setup message SETUP in which the information to be set is set is transmitted to ISDN.

As a result, a call setup message SETUP having the same content as that transmitted by the calling terminal is transmitted from the ISDN to the transfer terminal.

The transfer terminal analyzes the contents of the call setup message SETUP, and if the information indicating the release of transfer mode is included in the "user / user" information element, a release completion message is released to release the call connection. Respond REL_COMP.

A release completion message REL_CO responding at this time
As the content of the “user / user” information element of the MP, response information indicating that the content of the call setup message SETUP is acknowledged is set.

Upon receiving the release completion message REL_COMP from ISDN, the calling terminal releases the call connection at that time.

On the other hand, the transfer terminal cancels the transfer mode set therein, turns off the lamp 4g, and deletes the transfer destination telephone number.

In this way, the transfer mode set for the transfer terminal can be released by an operation from another ISDN telephone.

Similarly, the transfer destination telephone number set in the transfer terminal can be reset from another ISDN telephone.

In this case, the transfer reset key 4f of the ISDN telephone is turned on.

As a result, for example, guidance such as "Please input the telephone number of the telephone to which the transfer destination is to be reset and turn on the set key 4b" is displayed on the liquid crystal display 4h.

In response to this guidance display, the operator operates the numeric keypad to input the telephone number of the transfer destination to be reset, and turns on the set key 4b. Enter the telephone number above and turn on the set key 4b. "Is displayed on the LCD 4h.

When the operator operates the numeric keypad to input the telephone number of the telephone newly designated as the transfer destination and turns on the set key 4b, the ISDN telephone starts a calling operation.

That is, similarly to FIG. 7, the telephone number of the own terminal is set in the “calling number” information element, the telephone number of the transfer terminal is set in the “destination number” information element, and the transfer mode is reset in the “user / user” information element. A call setup message SETUP containing the information to represent and the telephone number of the telephone set as the new transfer destination
Send to SDN.

As a result, a call setup message SETUP having the same content as that transmitted by the calling terminal is transmitted from the ISDN to the transfer terminal.

The transfer terminal analyzes the contents of the call setup message SETUP, and if the "user / user" information element includes information indicating the transfer mode reset and the telephone number of the telephone set as the new transfer destination, Responds with a release complete message REL_COMP to release the call connection.

This releases the call connection between the calling terminal and the transfer terminal as described above.

Further, the transfer terminal changes the contents set as the transfer destination telephone number up to that time to the telephone number notified at that time.

In this manner, the transfer destination telephone number set in the transfer terminal can be changed by an operation from another ISDN telephone.

Therefore, for example, when the operator moves from the first destination to the next destination, the incoming of the transfer terminal can be transferred to the telephone of the next destination, which is very convenient.

By the way, in the embodiment described above, the case where the ISDN telephone is connected to ISDN is described, but the present invention can be similarly applied to the case where the ISDN telephone is connected to a private branch exchange having an ISDN function.

[Effect of the Invention] As described above, according to the present invention, as a transmission path
In an ISDN telephone terminal using ISDN, a transfer destination input means for operating and inputting a transfer destination, a transfer destination storage means for storing a transfer destination inputted from the transfer destination input means, and a transfer mode set in another terminal A call to the destination transfer in a state where a call signal is answered to the calling terminal when an incoming call is detected, and when the transfer destination answers the incoming call, the incoming call is answered to the calling terminal and the setting is made between the calling terminal and the calling terminal. First
And the information received via the second information channel is transmitted to the transfer destination via the second information channel set between the information terminal and the transfer terminal. While performing transfer control for sending to the calling terminal via the channel, when receiving, via the signal channel, transfer cancellation information from the calling terminal when the incoming call is detected, the transfer cancellation operation means is operated. A control means for preventing transfer control is provided, so that the call of the calling terminal can be transferred to a predetermined transfer destination, and even if the operator is not present, the caller of the calling terminal and the operator of the own terminal can be transferred. A call can be made, and the transfer operation can be stopped from another terminal. If the transfer operation becomes unnecessary, the transfer operation can be stopped immediately. Such an effect that very come in handy.

Further, in an ISDN telephone terminal using ISDN as a transmission path, a transfer destination input means for operating and inputting a transfer destination, a transfer destination storage means for storing a transfer destination input from the transfer destination input means, and setting in another terminal Transfer canceling operation means for canceling the transfer mode being set, and calling the destination transfer in a state in which a call signal is responded to the calling terminal when an incoming call is detected. And sends the information received via the first information channel set between the terminal and the transfer terminal to the transfer destination via the second information channel set between the terminal and the transfer terminal. Transfer control for transmitting the received information to the calling terminal via the first information channel, and transferring cancellation information by operating the transfer canceling operation means from the calling terminal when an incoming call is detected. When receiving over the signal channel, and thereafter, as well as to not to perform the above-described transfer control, after the transfer release, when receiving the information representing the transfer reconfiguration from the calling terminal when the call detected, thereafter,
Since the control means for resetting to perform the transfer control is provided, the call of the calling terminal can be transferred to a predetermined transfer destination, the transfer can be released from another terminal, and further, after the transfer is released. Since the remote operation can be performed to reset the transfer operation, the effect of canceling and resetting the transfer operation becomes very convenient.

Further, in an ISDN telephone terminal using ISDN as a transmission path, a transfer destination input means for operating and inputting a transfer destination, a transfer destination storage means for storing a transfer destination input from the transfer destination input means, and setting in another terminal A call release operation means for canceling the transfer mode being performed, and calling the destination transfer in a state where a call signal is responded to the calling terminal when an incoming call is detected, and when the transfer destination answers the incoming call, answering the incoming call to the calling terminal,
Sending the information received via the first information channel set up with the calling terminal to the transfer destination via the second information channel set up with the transferring terminal and the second information channel While transmitting control to transmit the information received via the first information channel to the calling terminal via the first information channel, the calling terminal transmits a signal indicating that the transfer canceling operation means has been operated by the calling terminal when an incoming call is detected. When receiving via the channel, the transfer control is not performed thereafter, and when the transfer destination is busy and the call is not answered, the call connection with the calling terminal is not performed and the transfer destination can answer the call. Is provided, a control means is provided for notifying that a call has been made by the calling terminal, so that the call of the calling terminal can be transferred to a predetermined transfer destination and transferred from another terminal. Removal can be further, if the transfer destination is busy, when the transfer destination becomes capable of responding state,
Since the transfer destination is notified that the call has been made from the calling terminal,
The transfer destination can make a call to the calling terminal, and the effect that the operator of the calling terminal can make a desired call can be obtained.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an ISDN telephone according to an embodiment of the present invention, FIG. 2 is a schematic diagram showing an example of an operation display unit, FIG. 3 is a time chart showing a basic procedure example of the ISDN telephone, FIG. 4 (a) is a schematic diagram illustrating a signal format of a message for a call setup procedure, FIG. 4 (b) is a schematic diagram showing an example of information elements of the call setup message, and FIG. 4 (c) is a release completion message FIG. 5 is a time chart showing an example of a procedure at the time of transfer, FIG. 6 is a time chart showing an example of a procedure at the time of transfer failure, and FIG. It is a time chart which shows the example of a procedure at the time of remote control. 1 CPU (Central Processing Unit), 2 ROM (Read Only Memory), 3 RAM (Random Access Memory), 4 Operation Display Unit, 4d Transfer Destination Input Key, 4e …
… Transfer release key, 4f …… Transfer reset key, 4g …… Lamp.

──────────────────────────────────────────────────続 き Continuation of front page (56) References JP-A-63-152251 (JP, A) JP-A-63-269847 (JP, A) JP-A-2-134948 (JP, A) JP-A-62 126753 (JP, A) JP-A-63-15558 (JP, A) JP-A-1-120161 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) H04M 1/00 H04M 1 / 24 H04M 1/58-1/62 H04M 1/66-1/78 H04M 3/42-3/58

Claims (3)

(57) [Claims] 1. An ISDN telephone terminal using ISDN as a transmission path, a transfer destination input means for operating and inputting a transfer destination, a transfer destination storage means for storing a transfer destination input from the transfer destination input means, and A transfer release operation means for releasing the transfer mode set in the terminal, and a call to the destination transfer in a state where a call signal is answered to the calling terminal when an incoming call is detected. Transmitting the information received through the first information channel set up with the calling terminal to the transfer destination through the second information channel set up with the transfer terminal, and transmitting the second information While performing transfer control for transmitting information received via the channel to the calling terminal via the first information channel, transferring when the transfer cancel operation means is operated by the calling terminal when an incoming call is detected. When removal information received via the signaling channel, thereafter, ISDN, characterized in that it comprises a control unit not to perform the transfer control
Phone terminal. 2. An ISDN telephone terminal using ISDN as a transmission path, a transfer destination input means for operating and inputting a transfer destination, a transfer destination storage means for storing a transfer destination input from the transfer destination input means, and A transfer release operation means for releasing the transfer mode set in the terminal, and a call to the destination transfer in a state where a call signal is answered to the calling terminal when an incoming call is detected. Transmitting the information received through the first information channel set up with the calling terminal to the transfer destination through the second information channel set up with the transfer terminal, and transmitting the second information While performing transfer control for transmitting information received via the channel to the calling terminal via the first information channel, transferring when the transfer cancel operation means is operated by the calling terminal when an incoming call is detected. When the transfer information is received via the signal channel, the transfer control is not performed thereafter, and after the transfer is released, when the information indicating the transfer resetting is received from the calling terminal when the incoming call is detected, the transfer control is thereafter performed. An ISDN telephone terminal, further comprising control means for resetting the transfer control. 3. An ISDN telephone terminal using ISDN as a transmission path, a transfer destination input means for operating and inputting a transfer destination, a transfer destination storage means for storing a transfer destination inputted from the transfer destination input means, and A transfer release operation means for releasing the transfer mode set in the terminal, and a call is transmitted to the destination transfer in a state where a call signal is responded to the calling terminal when an incoming call is detected, and the call is received by the calling terminal when the transfer destination responds to the incoming call. Responding and transmitting the information received via the first information channel set up with the calling terminal to the transfer destination via the second information channel set up with the transfer terminal, While performing transfer control for transmitting information received via the information channel of the above to the calling terminal via the first information channel, it is determined that the transfer canceling operation means is operated by the calling terminal when an incoming call is detected. When the transfer release information is received via the signaling channel, the above transfer control is not performed thereafter. When the transfer destination is busy and there is no incoming call response, the call connection with the calling terminal is not performed and the transfer destination is not transferred. An ISDN telephone terminal comprising control means for notifying that a call has been made by a calling terminal when a call can be answered.